FIG. 1.

Survival of C. jejuni 81-176 in monocytic cell cultures. C. jejuni 81-176 was added to 28SC human monocytic cells grown in Iscove's modified Dulbecco's medium with 4 mM l-glutamine at an MOI of 100 bacteria to each monocyte. After a 2-h infection, extracellular campylobacters were killed with gentamicin (100 μg/ml) for an additional 2 h, and the cells were washed and resuspended in medium free of antibiotics. At the indicated time points, culture cells were harvested and lysed with 0.2% Triton X-100. Viable campylobacters were enumerated by plate counts. Assay controls were established by culturing the inoculating dose of 81-176 in tissue culture medium without monocytic cells. ▴, 81-176-infected 28SC cells; ×, 81-176 control cultured without 28SC cells. The data represent the mean and standard deviation of three independent experiments.